INDUSTRIAL SUPPORT SERVICES SPECIAL SECTION
Sonny Kula | Elko International
Maintenance: Key to Production
Proper rig care spells less down time for oil producers
By Rindi White
F

rom spearing new prehistoric pools of crude oil to reworking a field to extract oil deposits previously untapped, drilling rigs are the machines that power the oil and gas industry. But, like any machine, they require significant maintenance and care to keep operating at maximum efficiency.

That’s one goal, says Luke Lawrence, wells manager for ConocoPhillips Alaska. And it’s an important one.

“For us, time is money. If the rig is efficient and is able to operate during the time we’ve planned it to operate, that’s better business for us. We do a lot of auditing and checking on how [rig owners] go about their maintenance processes. In our evaluation of a competitive tender, that’s part of what we look at,” Lawrence says.

A properly maintained rig is also safer for employees—that’s why the state Department of Labor and Workforce Development sets out Petroleum Drilling and Production Standards that specify proper operating conditions and prescribe various maintenance standards.

But how does it play out in the oil field? Who actually does the maintenance? And what does it take to do it?

Lawrence says his company—a producer—generally contracts with a rig operator, like Doyon Drilling, Nabors, or Nordic Calista. He likens it to a rental car agreement: ConocoPhillips is renting the rig, but the rig owner is responsible for ongoing maintenance.

The length of each contract varies according to use: a rig used for an exploration program might be under a seasonal contract, while a rig used for working over an old field might have a longer contract.

“In Alaska, we typically have what we consider long-term contracts. Maybe they run for a few years or have options to extend them,” Lawrence says. “That can vary according to where you are in the world; some might be for one well, others might be for a scope of ‘x’ wells, others might be time-based.”

The drillers, for their part, design and create rigs specifically for use in Alaska. Nordic Calista, for example, designs its own rigs and contracts with specialty rig engineering and manufacturing companies in the United States and Canada to develop each rig to Nordic’s specifications. Nordic Calista General Manager Udo Cassee says the company has four rigs capable of doing well maintenance (called workovers) drilling or exploration work on the North Slope. Maintenance rigs typically operate year-round, he says, while exploration rigs often have shorter contracts.

Proper Maintenance Is the Best Insurance

Provisions for maintenance are generally included in the contract, Lawrence says. For example, a contract might state that the rig will be shut down for thirty minutes each day for scheduled maintenance, or it might set out a longer shutdown to perform more significant repairs.

What happens during those dedicated maintenance periods varies, Cassee says.

“A drilling rig is a combination of a lot of things. An arctic drilling rig consists of the arctic structure, then power generation—generators—then power distribution, then a heating system, then the equipment to drill,” Cassee says.

A crew reinstalls a refurbished derrick on Nordic Calista’s Rig 2.

Dave Hiler, Toolpusher | Nordic Calista

Maintenance is continual, he says. Nordic Calista’s maintenance program specifies daily checks on various components of rig equipment, coupled with less frequent checks on other pieces. Most maintenance programs are similar across the board, Cassee says, whether the rig is operating in summer or winter, on the North Slope or in Cook Inlet. All conform to state regulations, American Petroleum Institute standards, and other industry standards.

One example, he says, is the “slip and cut” program. A large portion of drilling is running pipe in or out of a hole with the drawworks, a hoisting system. As a precaution against drilling line failure due to fatigue, the work done by the drilling line is closely monitored and limited. After a predetermined limit of induced fatigue, new line is unspooled from the storage reel and slipped through to move the fatigued sections of line.

A crew reinstalls a refurbished derrick on Nordic Calista’s Rig 2.

Dave Hiler, Toolpusher | Nordic Calista

A crew reinstalls a refurbished derrick on Nordic Calista’s Rig 2

Maintenance is continual, he says. Nordic Calista’s maintenance program specifies daily checks on various components of rig equipment, coupled with less frequent checks on other pieces. Most maintenance programs are similar across the board, Cassee says, whether the rig is operating in summer or winter, on the North Slope or in Cook Inlet. All conform to state regulations, American Petroleum Institute standards, and other industry standards.

One example, he says, is the “slip and cut” program. A large portion of drilling is running pipe in or out of a hole with the drawworks, a hoisting system. As a precaution against drilling line failure due to fatigue, the work done by the drilling line is closely monitored and limited. After a predetermined limit of induced fatigue, new line is unspooled from the storage reel and slipped through to move the fatigued sections of line.

“We do that until we have to replace the whole drill line,” Cassee says.

Blowout preventers, or BOPs, are another carefully maintained item. They must be tested every seven to fourteen days, depending on the operation. Testing them is a five- to six-hour process, Cassee says. In addition to regular testing, the BOPs must be regularly inspected either by the manufacturer or with their supervision; every five years they must be removed and completely disassembled, inspected, repaired, and readied for use again. The BOP is a combination of rams that seal around the drillpipe to close in a well during a well control event.

A key to efficient maintenance, Cassee says, is standardization. If the same basic parts are used across all four of Nordic Calista’s rigs, it makes it more efficient to maintain them and easier to maintain stock of replacement parts on hand. Each rig carries normal maintenance parts, he says, along with critical parts to allow for onsite repairs as much as possible. While the goal is for most repairs to be made onsite, sometimes a complex issue will mean a component must be sent to Anchorage to be rebuilt or repaired.

Remote vs. Rural Operations

While maintenance schedules and the tasks needed to keep a drilling rig operating well don’t differ much between Prudhoe Bay and Cook Inlet—Alaska’s two primary drilling locations—there are many other differences. Ryan Peterkin is president and owner of MagTec Alaska, a full oil field service company that provides drilling support and production support. MagTec operates out of both locations year-round.

Peterkin says operating in the Cook Inlet region is generally more restrictive than operating on the Slope. Companies hauling rig pieces and equipment or otherwise servicing rigs in eastern Cook Inlet must adhere to Alaska Department of Transportation & Public Facilities’ size and weight restrictions and deal with overhead power lines, among other things.

“We’re usually restricted to haul around 100,000 pounds a load,” Peterkin says. “You can easily run 800,000 pounds a load in Prudhoe Bay. A normal vacuum truck, often used in servicing, holds typically 100 barrels on the Peninsula; it’s 300 barrels in Prudhoe Bay,” he says.

Vacuum trucks are used for several purposes: to haul drilling mud to a drill site, to bring fresh water for making drilling mud, or they might haul drill cuttings away from the drill site for disposal. The same activities must happen at a drill site on the North Slope or Cook Inlet, he notes, but operating in eastern Cook Inlet might mean having to use more trucks to do so.

The “legal load” requirement on Department of Transportation & Public Facilities-maintained roads also means a slightly different drilling season in eastern Cook Inlet, Peterkin says.

“Really, the rigs don’t start moving until about June 1,” he says, due to post-winter breakup conditions that lead to reduced-weight loads on roads around the state.

Rigs in Cook Inlet tend to be smaller than those on the North Slope, but at roughly a million pounds, they’re still larger than most rigs in North America, Peterkin says. Even though they might operate mostly in summer, they are still fully enclosed and winterized.

Road restrictions don’t come into play as much for operations on the western side of Cook Inlet—Beluga and Tyonek and south to Drift River—and on offshore rigs within the inlet. Different restrictions are in place there: all equipment and supplies, from drilling mud to food, must be carried by service boats or flown in.

The floor of Nordic Calista’s Rig 2 during refurbishment.

Nordic Calista

The floor of Nordic Calista’s Rig 2 during refurbishment
The floor of Nordic Calista’s Rig 2 during refurbishment.

Nordic Calista

ConocoPhillips Alaska is using Doyon Drilling’s Extended Reach Drill rig, called Doyon 26.

Judy Patrick | ConocoPhillips Alaska

ConocoPhillips Alaska is using Doyon Drilling’s Extended Reach Drill rig, called Doyon 26.

Judy Patrick | ConocoPhillips Alaska

ConocoPhillips Alaska is using Doyon Drilling’s Extended Reach Drill rig, called Doyon 26
A crew raises the mast after rig startup on Nordic Calista’s Rig 2.

Nordic Calista

A crew raises the mast after rig startup on Nordic Calista’s Rig 2.

Nordic Calista

A crew raises the mast after rig startup on Nordic Calista’s Rig 2
It Takes a Village

ConocoPhillips’ Lawrence estimates it takes around 100 people to operate a drilling rig. Although fewer than 10 people might be at work at one time on the rig, Cassee explains that two shifts are needed to keep it running around the clock. With typical rotational schedules of two weeks on and two weeks off, that means a total of four crews are employed in basic rig operations. But that’s just the start.

There are people who clean the snow off the rig and people who bring in water, both potable for use in the man camp and water for the drilling operation. There are caterers and cleaners and companies that provide waste removal.

“The supportive crew—doing the trucking, bringing water and fuel, bringing mud, all the testers, the tooling guys—it’s never smaller than 300 people,” says Jeff Miller, vice president of operations for Cruz Construction.

Cruz is one of a half-dozen companies providing comprehensive oil field support services—similar to MagTec, Arctic Slope Regional Corporation, Worley, and Northern Energy Services.

“If you’re adding in the people in Anchorage, working for parts stores, et cetera, it’s a significant amount of people,” Cassee says.

A 2020 report by McKinley Research about the role of the oil and gas industry in Alaska’s economy states that, according to 2018 figures, about 4,111 Alaska residents worked for the seventeen primary oil companies the report identified as working in Alaska at the time. Another 5,800 Alaska residents worked in oil field support jobs, and 31,900 more worked in indirect and induced jobs—for example, companies that provide goods to oil production companies or jobs and income generated when oil workers or those in oil field support jobs spend money in the local economy. For each $1 earned by an employee of a primary oil producer, $4 in indirect and induced wages are generated in the state, the study reports.

Operating with an Eye on the Environment

Oil production generates waste, as do maintenance activities.

Cassee says if Nordic Calista is operating under a contract, some waste removal responsibility falls under the purview of the operator. If that’s the case, his crew separates waste at the rig site and the operator oversees disposal. If his crew is in Deadhorse and not working with a client, the waste is handled by the North Slope Borough.

“We make a really good effort to segregate all the waste: recycling and reusing everything we can,” Lawrence says of ConocoPhillips Alaska. While waste collection and segregation on the working rig is the responsibility of the rig owner, the operator—ConocoPhillips Alaska in this case—handles transportation from the drilling site to the disposal location.

Not all waste has to be handled off-site. Peterkin says drill cuttings, for example, are primarily ground up gravel. If it has no sheen of contamination, the cuttings are cleaned and reinjected. Some of the waste—contaminated glycol, for example—is handled by environmental waste handler NRC.

All waste is handled according to the Alaska Waste Disposal and Reuse Guide, referred to as the “Red Book,” which guides how oil and gas drilling waste should be properly disposed.